The engagement of additive manufacturing (AM) technology in developing intermetallic coatings involves additional heat treatment with a view to obtaining desirable microstructure and mechanical properties. This eventually increases the lead time and the manufacturing cost. To address these challenges, this study explores the fabrication of gradient and laminar structures of titanium aluminide (Ti-Al) composite coatings deposited on Ti-6Al-4V substrate via a single step laser cladding (LC). The alterations in microstructural properties, chemical composition and phase analysis of the coatings reinforced with TiC were investigated as a function of laser energy density. Evaluation of the deposited samples reveals that FGM composite clads were fabricated from Ti-Al blended with TiC when LED was set at 17.50 J/mm2. At the selected LED, a thermo-positive reaction between the constituents’ materials was induced and it resulted in the formation of intermetallic compounds (e.g. Ti2AlC, and 2 matrix phases) with a microhardness more than that of the substrate (Ti-6Al-4V alloy). This study provides new insights on the selection of process parameters for the coating manufacturers while employing low cost- and time-effective LC process for fabricating functional graded Ti-Al coatings.
Reference:
Olakanmi, E.O. et al. 2018. Effect of energy density on the consolidation mechanism and microstructural evolution of laser cladded functionally-graded composite Ti-Al system. Solid Freeform fabrication 2018: Proceedings of the 29th Annual International Solid Freeform fabrication symposium- An additive Manufacturing Conference: Reviewed Paper, Austin, Texas, USA, 13-15 August 2018, pp. 1422-1438
Olakanmi, E., Sepako, M., Morake, J., Kutua, S., Hoosain, S. E., & Pityana, S. L. (2018). Effect of energy density on the consolidation mechanism and microstructural evolution of laser cladded functionally-graded composite Ti-Al system. http://hdl.handle.net/10204/10623
Olakanmi, EO, M Sepako, J Morake, S Kutua, Shaik E Hoosain, and Sisa L Pityana. "Effect of energy density on the consolidation mechanism and microstructural evolution of laser cladded functionally-graded composite Ti-Al system." (2018): http://hdl.handle.net/10204/10623
Olakanmi E, Sepako M, Morake J, Kutua S, Hoosain SE, Pityana SL, Effect of energy density on the consolidation mechanism and microstructural evolution of laser cladded functionally-graded composite Ti-Al system; 2018. http://hdl.handle.net/10204/10623 .
Paper presented at the 29th Annual International Solid Freeform fabrication symposium- An additive Manufacturing Conference: Reviewed Paper, Austin, Texas, USA, 13-15 August 2018